#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main (int argc, char const* argv[])
{
    int c, i, j, len;
    char buf[256];

    while (EOF != scanf("%d", &c)) {
        if (c == 0) break;

        scanf("%s", buf);
        len = strlen(buf);

        for (i = 0; i < len / c; i++) {
            if (i % 2 != 0) {
                for (j = 0; j < c / 2; j++) {
                    int t = buf[i * c + j];
                    buf[i * c + j] = buf[i * c + (c - j - 1)];
                    buf[i * c + (c - j - 1)] = t;
                }
            }
        }

        for (i = 0; i < c; i++) {
            j = i;
            while (j < len) {
                printf("%c", buf[j]);
                j += c;
            }
        }
        printf("\n");
    }

    return 0;
}
